Pump plunger



Feb. 22, 1949. .1. D. CUNNINGHAM PUMP PLUNGER Filed Sept. 19, 1944 INVENTOR. JTDGUNNINGHAM fiTTO/PNEY.

Patented Feb. 22, 1949 UNITED STATES ?ATENT OFFICE PUMP PLUNGER John D. Cunningham, Houston, Tex. Application September 19, 1944, Serial No. 554,801

9 Claims.

The invention relates to a pump plunger and a cage therefor of the type employed in pumping liquids from deep wells.

A pump plunger disposed in a well bore is usually reciprocated in a pipe or tubing known as the working barrel. The gas, oil, and water being drawn from the earth formation carry a proportion of sand or other abrasive materials which shorten the life of the pump plunger and the working barrel. Various expedients have been employed in attempting to avoid wear and abrasion; and the present invention has been devised with the view of avoiding wear due to any sand or gritty substances or metal-to-metal contact between the pump plunger and cage and the working barrel.

It is, therefore, one of the objects of the present invention to provide a pump plunger and cage where the metal parts are insulated from contact with the working barrel by a non-metallic material.

Another object of the invention is to provide a pump plunger and cage where the packing and contacting surfaces on the periphery thereof are of non-metallic material,

Another object of the invention is to provide a pump plunger having packing rings thereon supported in spaced relation by a sleeve of nonmetallic material.

Another object of the invention is to provide a cage for pump plungers wherein an insulating sleeve makes contact with the working barrel to avoid abrasion, andto also direct abrasive materials into the upwardly flowing stream of pumped liquid to prevent an accumulation thereof.

Another object of the invention is to provide a non-metallic sleeve for pump plungers and pump cages wherein the liquid being pumped will tend to hold such sleeve in engagement with the working barrel.

Still another object of the invention is to provide a pump plunger and cage which will operate for long periods of time without wear due to abrasion.

Other and further objects of the invention will be readily apparent when the following description is considered in connection with the accompanying drawings, wherein:

Fig. 1 is a vertical, sectional view of the working barrel, pump plunger, and cage construction.

Figs, 2 and 3 are sections taken on the line 2-4 and 3--3, respectively, of Fig. 1.

In Fig. l the pipe or tubing 2 is usually disposed in the well bore and may have a working surface 3 upon which the pump plunger 4 is arranged to reciprocate in effecting the pumping action.

The plunger 4 is usually reciprocated by a string of sucker rods extending to the surface, and these rods will b connected to the threaded stud 6 formed on the upper end of a cage 1, which is in turn threaded at 8 to the body 9 of the pump plunger.

As is usual with such pumps, a standing valve comprising a ball and seat is positioned in the pipe 2 below the elevation shown on the drawing. The plunger 45 carries a ball valve ID and the seat H, which will close upon upward movement of the plunger and draw a charge of liquid from the well into the area I 4 in the working barrel 2. On the down-stroke, the standing valve will close and the liquid accumulated in the chamber [4 will be forced through the passage is in the hollow body 9 of the pump. This will cause th ball H! to be lifted from its seat so that the flow of fluid may pass upwardly through the plunger and through the cage l by means of the windows 20, three of which are seen in Fig. 2.

In the operation thus described, it seems obvious that any sand or solid matter carried by the liquid being pumped will have a tendency to settle out of the liquid as it moves into the working barrel above the plunger.

The present plunger and cage contemplate a novel arrangement whereby the metal portions of the plunger and the cage will be spaced from the surface 3 of the working barrel so as to avoid abrasion due to sand or other solid matter working in between the plunger and the surface of the working barrel.

The cage body 1 is in the form of an inverted cup threaded at 8 on the upper end of the plunger body 9. This cage has an outer periphery 2! which is of less diameter than that of the working barrel, so that an annular sleeve 22, positioned on the periphery of the metal portion of the cage, serves to fill the space and form a seal with the surface of the working barrel. In Fig. 1 this sleeve is shown as having a plurality of grooves 23 in its periphery so as to catch any solid matter working down along the outside and to trap some liquid which will serve to lubricate the sliding action. This sleeve 22 may be of any suitable non-metallic material. It is contemplated that it may be of plastic or other suitable material such as rubber, either natural or synthetic, or any material which will resist deterioration due to being immersed in oil, water, or gas. This sleeve is preferably afiixed by suitably molding it upon the periphery of the cage 1, but it ma be otherwise aflixed.

The upper edge of the cage 1 is cut away at 21 to form a pocket so that the liquid being pumped may exert a pressure against the upper edge of the sleeve 22 and force it against the surface of the working barrel. The upper edge 28 of the sleeve may be beveled inwardly so that any solid matter which is encountered will be driven inwardly into the upwardly flowing stream of liquid through the windows 20. The sleeve 22 encloses the windows 29 and the pockets 21 so as to prevent any accumulation of solid matter therein.

It has been found that in actual practice a suitable synthetic rubber applied or bonded to the surface of the cage results in extended service, the elimination of abrasion, and the constant removal of the solid matter.

In order to protect the pump plunger body 9, the periphery of the body portion has been reduced in size as at 30, which creates a flange 3|, against which the cage I and the sleeve 22 are arranged to engage.

The lower surface of the flange 3| serves as a seat for a packing ring 32 against which is deposited the spacer ring 36 and a second packing 35. This packing set or assembly is then held in place by a collar 3'! which slips over the periphery of the body 9 and is arranged to abut the lower packing 35. If desired, a liquid trap 38 is provided by cutting away the upper edge of the collar 37.

To insulate the body of the pump plunger from the working barrel surface, a sleeve 40 of the same material as the sleeve 22 is disposed about the collar 31 so as to serve as a support for the lower, outer edge of the second packing 35.

A similar and identical set of packing M is shown at the lower end of the collar 31, and this second set 4| is held in place by a nipple 42, threaded at 43 on the lower end of the plunger body 9.

To complete the insulation, a sleeve 45 of non-metallic material, the same as previously described, is disposed about the nipple 42 and supports the lower edge 45 of the lower set of packing 4|.

The sleeves 40 and 45 tend to hold the packing rings against undue flexing which results in greater service.

It has been found that a pump plunger constructed in connection with the foregoing description prevents the accumulation of solid matter in the pump, extends the satisfactory working life of the working barrel and the plunger, and results in extended operation, which avoids servicing of the well to renew the packing rings and sealing member.

Broadly, the invention contemplates a combination plunger and cage which are insulated from the surface of the working barrel to avoid abrasion.

What is claimed is:

1. A plunger for well pumps comprising a body, a. plurality of spaced packings thereon providing exposed areas of said body which are not covered by said packings, means to retain said packings on said body, and sleeves of non-metallic material about said body over the exposed areas thereof whereby wear on the plunger and well pump are minimized.

2. A plunger for well pumps comprising a body, a plurality of spaced packings thereon providing exposed areas of said body which are not covered by said packings, means to retain said packings on said body, and sleeves of nonmetallic material about said body over the exposed areas thereof whereby wear on the plunger and well pump are minimized, said sleeves abutting said packings.

3. A pump plunger assembly including a body, a flange thereon, a set of packings against said flange including a spacer ring and a second packing, a support collar against said second packing, said collar being of less diameter than said packing, an insulating sleeve on said collar flush with the packings, a second set of packings, and means to retain said parts against said flange.

4. A pump plunger assembly including a body, a flange thereon, a set of packings against said flange including a spacer ring and a second packing, a support collar against said second packing, said collar being of less diameter than said packing, an insulating sleeve on said collar flush with the packings, a second set of packings, means to retain said parts against said flange, and an insulating sleeve on said means so that there is no exposed metal on the outer periphery of said plunger.

5. A hollow pump plunger for wells including a body, a packing, sealing and insulating assembly about the periphery of said body, including a resilient covering on the body above and below the packings; a flange on the body to receive one end of the assembly, and a nipple on the other end of the body to retain said assembly.

6. A hollow pump plunger for wells including a body, a packing, sealing and insulating assembly about the periphery of said body, including a resilient covering on the body above and below the packings; a flange on the body to receive one end of the assembly, and a nipple on the other end of the body to retain said assembly, said assembly including a non-metallic sleeve disposed between spaced packing rings.

7. A cage for deep well pump plungers including an inverted cup body, means to connect the body to a pump plunger, means to connect the cage to a sucker rod, flow windows in the sides and top of said body, and a sleeve of non- I metallic material about said body.

8. A cage for deep well pump plungers including an inverted cup body, means to connect the body to a pump plunger, means to connect the cage to a sucker rod, flow windows in the sides and top of said body, and a sleeve of nonmetallic material about said body, said sleeve extending above said body to direct sand and solid matter into the upflowing stream of pumped liquid.

9. A cage for deep well pump plungers including an inverted cup body, means to connect the body to a pump plunger, means to connect the cage to a sucker rod, flow windows in the sides and top of said body, and a sleeve of nonmetallic material about said body, said sleeve extending above said body to direct sand and solid matter into the upflowing stream of pumped liquid, and pockets to receive solid matter intermediate said windows.

JOHN D. CUNNINGHAM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Kater et al Oct. 17, 

